Retrieval apparatus for die casting equipment

ABSTRACT

A retrieval apparatus for die casting equipment which includes an extension tube for reaching into a die casting machine carrying an extension bar for increasing the range of the reach, there being pick-up jaws on the extension bar for clamping an ejected casting and returning it to a drop position over a quench tank, the jaws being movable to change the position of the casting so that it will orient properly with the quench tank and thus reduce the spacing required for the assembly. A mechanism for actuating the jaws from a release position to a pick-up position and again back to a release position together with a locking means for the jaws is incorporated to operate automatically during the extension and retraction motion of the slide tube and slide bar, and safety release mounting means are provided for the assembly to avoid damage due to possible malfunction.

United States Patent Canner I 1 June 13, 1972 [54] RETRIEVAL APPARATUSFOR DIE 3,586,176 6/1971 Rackman et al ..2l4/l B CASTING EQUIPMENTPrimary Examiner-William F. ODea [72] Inventor: Herman M. Canner,Detroit, Mich. Assismm Examine, wes|ey R tliff Jr. [73] Assignee:Sterling Detroit Company, Detroit, Mich. A"0mey Bames' Ra'sch Choate[22] Filed: July 1, 1970 [57] ABSTRACT [21] Appl.No.: 51,528 A retrievalapparatus for die casting equipment which includes an extension tube forreaching into a die casting 52 us. (:1. ....74/s9.17, 214/1 BB, 214/1 CMmachine carrying i increasing [51] Int Cl F16]! 27/02 the reach, therebeing pick-up aws on the extension bar for 58 Field of Search .....211/1 B, 1 13B, 1 ET, 1 CM; clamping ejected and rimming a dmp over aquench tank, the aws being movable to change the 74/89.l7

position of the casting so that It will orient properly with the quenchtank and thus reduce the spacing required for the as- [56] ReferencesCited sembly. A mechanism for actuating the jaws from a release UNITEDSTATES PATENTS position to a pick-up position and again back to arelease position together with a locking means for the jaws isincorporated Chambers t at a tomati ally during the extension andretraction 3,033,059 5/ 1962 Melton et -214/1CM motion of the slide tubeand slide bar, and safety release 3,107,402 10/1963 Hunter ..2l4/l BBmounting means are provided f the assembly to avoid 3,262,593 7/1966Hamer... ..214/1 CM damage due to possiue lf i 3,303,941 2/1967 Hanes..2l4/1 B 3,482,71 1 12/1969 Bohme et a1 ..2l4/1 CM 5 Claims, 16 DrawingFigures .PATENTEnJumi'sin 3.668841 sum 10F 9 FIG. 1

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SHEET 9 OF 9 INVENTOR MFR/MAN m. ("ANA/[R ATTO R N EYS This inventionrelates toRetrieval Apparatus for Die Casting Equipment and moreparticularly to an apparatus for retrieving completed castings which areejected from the molds of an automatic die casting machine.

The apparatus eliminates the necessity for an operator reaching in toretrieve the casting from the mold as it is ejected and thus preventsthe hazards that are incident to an operator extending his hands andarmsinto the area where moving parts might cause injury.

In order to simulate the actions of an operator and also provide safetyvehicles which prevent damage to the machine, that is, either theretrieval apparatus for the casting machine, it is necessary to havecertain safety controls and a construc tion which prevents damage in theevent of a maladjustment or accidental'cycling.

In a casting machine, the die consists of two parts which close duringthecasting and which open after the casting has cooled sufficiently thatit may be ejected by standard ejection equipment. In order that thecycle may continue as rapidly as possible, it is necessary that theretrieval apparatus synchronize with the motion of the dies to theextent that it may follow this motion and, in a sense, pick up thecasting as the dies are opening and remove it rapidly so that the-diesmay move into the next cycle without undue interruption.

It is, therefore, an object of the present invention to provide amachine which will perform this function and move synchronously with thedie opening action, pick up the casting and move it out of the die areawith proper acceleration and deceleration motion which will preventdamage to the casting or the possibility of accidental dislodgment.

Other objects and features of the invention include a double projectionarm with harmonic motion which provides power acceleration-decelerationcharacteristics, a swivel jaw which can change the part position as itreturns to a dump-quench position, anautomatic lock which insures properjaw position during pick up and a lock-release actuatedduringretraction, and a mechanism for relating the arm,.jaws, and lockfor interaction in proper sequence. j

Other objects and features of the invention will be apparent inthefollowing description and claims in which the principles of theinvention are disclosed together with the manner of use in connectionwith the best mode presently contemplated for the invention.

Drawings accompany the disclosure and the various views thereof may bebriefly described as:

FIG. I, perspective view of the overall machine showing the relationshipof the parts.

FIG. 2, a sectional view on line 2-2 of FIG. 1.

FIG. 3, a view on line 3-3 of FIG. 2.

FIG. 4, a sectional view on line 44 of FIG. 3.

FIG. 5, a segmental view of the machine showing a drive mechanism forthe fore and aft thrust arm.

FIG. 6, a top view of the drive taken on line 6-6 of FIG. 5.

FIG. 7, an enlarged view of the gripping jaw and the actuatingmechanism.

FIG. 8, a sectional view on line 8-8 of FIG. 7.

FIG. 9, a sectional view on line 9-9 of FIG. 8.

FIG. 10, a view on the outer end of the arm projection mechanism takenon line 10-10 of FIG. 7.

FIG. 11, a view of a portion of the mechanism of FIG. 10 showing certainparts in elevation.

FIG. 12, a sectional view on line 12-12 ofFIG. 11.

FIG. 13, a sectional view on line 13-13 of FIG. 10.

FIG. 14, a view similar to FIG. 13 showing the parts in a differentrelationship.

FIG. 15, a detail of a control mechanism within the extension arm.

FIG. 16, a detail of the jaw control of the mechanism.

REF ERRING TO THE DRAWINGS:

A machine base has suitable railmounts 22 to permit the retrievalapparatus to be mounted adjacent a molding machine. Generally, there isa quench tank between the base 20 and the molding or casting machine sothat the part may be removed from the molds, pulled away from themachine, and then dropped into a quench tank where it can be conveyed tothe next manufacturing operation.

A suitable control control box 24 is provided for controls which can beelectrical and hydraulic and follow standard conventional practice. Twoparallel mount bars 26 and 28, see FIG. 2, are mounted on the base 20and transversely of these bars are cross bars 30 and 32 suitablyanchored to the mount bars and connected by cylindrical guide rods 34and 36 forming horizontal ways. On these rods are cylindrical slides 38and 40, each of which carries, respectively, an upright 42 and 44connected by a cross mount plate 46.

This plate serves as an anchor for an adjustable piston rod 48 extendingfrom a piston cylinder assembly 50 mounted on the cross plate 32. On'thetop of the upright 42 is a swivel block 52 suitably pivoted for swingingon a vertical axis, there being a rigid relatively large bearing postanchored in upright 42 for carrying the swivel block 52, FIG. 3. On acantilever bar 54 are mounted suitable solenoid valves 56 and othercontrols which can be utilized for actuating the machine.

The vertically disposed swivel plate 60 is rigidly mounted on the swivelblock -52, this plate serving as an arm mount to carry the retrieval armand the mechanism for the pick-up of a molded part. This plate 60 isassociated with the other upright 44 in a manner illustrated especiallyin FIGS. 3, 4 and 5.

The top of the pillar 44 has a ride plate 62 which supports the bottomedge of plate 60, this edge being apertured at 64 to receive an eye-bolt66 held in place by a bolt 68. The eye-bolt passes through a housing 70and is affixed by a threaded connection to an arm 72 around which ismounted a compression spring 74. At the end of the arm 72 is a springretainer 76,

- FIG. 2, held in place by nuts 78. Thus, it will be seen that plate 60is pivotally mounted on the the upright 42 by the swivel block 52 heldin place on post 53 by a disc and the plate 60 is also supported on theride plate 62 but may move on this plate by reason of the pivot post 53on which the swivel block is mounted so that the entire plate may shiftaround the pivot axis restrained by the spring 74. The purpose of thisswivel mount is to allow some motion of the entire mount for theretrieval arm in the event of a malfunction or improper timing in theretrieval action.

Looking now at the top of the plate 60 there is found the mount for alarge rectangular tube 90, this being held in place by two rectangulanbrackets 92 and 94 having depending extensions 96 and 98 which aresuitably welded or bolted to the plate 60. These rectangular brackets orblocks 92 and 94 are designed to carry suitable roller mounts for theslide tube 100 as shown in the sectional view in FIG. 8.

A double roller 102 at the bottom of FIG. 8 on a common axis shaft 104is mounted in a journal block 106 to carry the bottom load of the tube100. Similarly on the left hand side, a double roller 108'on a shaft 110is mounted in a suitable bearing journal 112.

At the top of the mount is a double bearing roller 114 on a shaft 1 16mounted in ajournal block 120. In this instance, the journal block ismovable in a cavity 126 and its position is adjustable by a screw 128which can be locked by a nut 130. The opening in the journal block forthe shaft 116 is substantially larger than the shaft and is filled witha plurality of closely positioned rings 132 nestled adjacent each otheracross the shaft. The same construction is shown at the right-hand sideof the mount in FIG. 8 where rollers 134 are mounted on a shaft 136 in ajournal 138 which again carries the eye rings 140. On this side of thedevice, a screw 142 can adjust the block 138 and be locked by a nut 144.Thus, the journal block and the journal block 138 can be urged againstthe side walls of the tube 100 by a resilient pressure due to theresilience of the 0- rings which mount the bearing shafts.

It is very difficult without a great deal of expense to provide aprojection tube which has a constant dimension throughout its length andwhich has perfectly straight lines on the side walls. The mountdescribed in connection with FIG. 8 allows the tube 100 to pass throughthe bearings with a smooth, clean movement and the O-ring mount of thebearing shaft takes up the variation in the dimensions as the tubemoves. This provides a very inexpensive compensating bearing mount whichavoids the necessity for any springs in the unit. In the mounting block92 a similar bearing arrangement is provided.

The actuation of the slide tube 100 is achieved through a double armdrive as illustrated in FIGS. 1 and 5. The tube has a depending stud 150on which is pivotally mount an eye ring 152 which is adjustablyconnected with the end of a long arm 154 of a double arm drive. This armextends to the left as viewed in FIG. and connects through an adjustablepivot block 156 to a short arm 158. This short arm is socketed in apivot drive block 160 carried by a shaft 162 extending form a gear rackhousing 164 in which is mounted a gear 166 on shaft 162, and a rack 168,the latter being driven by a piston rod 170 of a piston cylinderassembly 172, FIG. 6.

Thus, actuation of the piston in the cylinder 172 can cause retractionof the slide 100 to one position as shown in FIG. 5 and an extension ofthe slide tube by the dimension equal to twice the distance between thecenter of the shaft 162 and the center of the pivot block 156, thisbeing adjustable. It will also be evident that this motion in both theforward and return action will be harmonic in the sense that it willstart with a low acceleration and gradually increase in its accelerationand then after the arm 158 passes the 90 mark in its travel, it willdecelerate to the end of the travel. Thus, a smooth movement of theslide tube 100 can be obtained by a suitable direction of pressure toone end or the other of the pressure cylinder combination 172. Themotion will be declerating at the part pickup position and also at thepart drop position.

A shown in FIG. 6, the housing 164 is mounted on plate 60 by a back wall174 of the casting, this being bolted on at 176.

- On either side of the block 160 are stop blocks 178 which can contactplate 160 to limit the motion of the arm 158. If desired, these blocksmay be capped with a resilient material to absorb shock.

The motion which is afforded by the swing of the arm 158 is notsufficicnt to reach over a quench trough and into the casting machine.Accordingly, there is mounted in the slide tube 100 a further extensibleunit to complete the necessary extension. The timing of this extensioncan either be simultaneous or sequential.

The secondary extension arm comprises a solid shaft 180 of square crosssection, actuated by a rod 182, extending from a piston cylinderassembly 184 at the rear end of the slide tube 100 (see FIG. 7). If theview of FIG. 1 is considered the front of the machine, the view of FIG.7 is from the rear or opposite side. The stroke of the slide bar orshaft 180, therefore, is dependent on the length of the cylinder 184.The slide bar is suitably mounted and guided in the slide tube 100.

At the forward end of the extension bar 180, as viewed in FIG. 7, is amount bar 186 for a jaw mechanism shown in detail in FIG. 16. Thismechanism has a jaw 188 which cooperates with a second jaw 190, thesebeing moved around mounting pivot pins 192 and 194 by toggle links 196and 198 actuated by a piston-cylinder combination 200 and an associatedpush-pull block 202. The entire jaw assembly is mounted on a pivot block204 carried on a shaft 206 mounted in bearings 208 and 210 in a housing212 carried on the mount bar 186.

Slidable in the housing 212 is a slide rack 214 which cooperates with arack gear 216 affixed to the shaft 206. Thus, the jaw assembly can berotated on a vertical axis from the position shown in FIG. 16 to aposition which is 90 away. When a casting is quite long, it is withdrawnwhen the jaws grab the central sprue and comes away from the castingmachine in plane transverse to the general axis. If a quench tank ispositioned between the casting machine and the retrieval apparatus, itwould have to be quite wide to receive the casting cross-wise of thetank. The pivoting of the jaws moves the casting so that it can bedropped into the machine lengthwise making it possible to use a narrowerquench tank and this saving floor space.

As shown in FIG. 10, the rack 214 has a stop dowel 218 fastened theretoand extending therefrom the outer end being controlled at the limits ofmovement by the ends of a groove 220 in a stop-plate 222. Thus, therotating shaft 206 is limited to a rotation. Accordingly, when the jaws188-190 have grasped the sprue plug 22 (FIGS. 7 and 16) and removed acasting, as viewed for example in FIG. 1, the jaws can be rotated 90 sothe casting will be positioned in a plane transverse of the direction ofmovement of the arm 180 so that it may be dropped into a quenchingtrough or tank in the proper orientation.

The actuation of the jaws for closing and opening by the piston-cylinderassembly 200 can be controlled by suitable limit switches andsolenoid-actuated valves as are commonly used in the industry.

The rotation of the jaws is accomplished at suitable times during theextension and retraction stroke of the extension bar 180 and there isprovided suitable locking mechanisms to stabilize the jaws in thepick-up position during the out movement. An actuator rod 230 whichparallels the bar 180, is fixed at the fore end to the rack block 214,FIGS. 10, 11 and at the aft end to a block 232 which rides on thetrailing end of the bar 180, FIGS. 8, 15. A bracket 234 within the tubesurrounds the bar as illustrated in FIG. 8, and this bracket carries aplunger 236 backed by a spring 238. The travel of the plunger is limitedby a cross-pin 240 and a notch 242. The length of the rod 230 relativeto the stroke of the extension bar is such that the heel block 232 ofthe rod 230 will be against the plunger compressing the spring when thebar is fully extended. This will retract the rack bar 214 and move thejaws to the grab" position, the rack in the retraced position beingshown in FIG. 11.

A latch 250 for the rack which locks the swivel head is shown in FIGS.10 to 14. This latch 250 slides up and down in block 212. In the down"position, it locks the rack 214 in the grab position of the jaws. SeeFIG. 13. In the up" position, FIG. 14, the rack can move to pivot thejaws to a release" position. The latch block is actuated to an upposition by a stationary finger 252, FIG. 7, which has a beveled end 254to cooperate with an overhang projection 256 on the latch block, FIGS.12,13,14.

The finger 252 is mounted on a bracket 258 carried by the forward end ofthe extension tube 100. It will be noted that as the block 212 retracts,the tapered end 254 of the finger 252 will enter below the overhang 256and lift the entire latch block. In FIG. 13, the latch block is shown inthe lock position wherein a projection 260 on the latch block enters anotch 262 in the rack 214 to prevent the rack from shifting. In FIG. 14,t latch 250 is shown in the lifted position wherein the projection 260is lifted out of the opening in the gear rack slide 214.

Thus, to review the general operation of the jaws and projection bar180, when the arm 180 is projected outwardly from the tube 100, thefinger 252 will slide out from under the latch 250. This will allow thelatch to drop so that the projection 260 can ride on the top of the rack214. As the arm 180 moves outwardly, the heel block 232 is stopped bythe plunger 236 and the continued motion of the arm 180 will draw backthe gear rack bar 214 to the position shown in FIG. 11. In thisposition, the latch 250 can drop to the locking position shown in FIG.13. Thus, the jaws will be locked in the position shown in FIG. 7 andwill move out to grab the sprue 224. Then upon the return of the jaws tothe position shown in FIG. 7, the nose 254 will have entered under theprojection 256 to lift the locking block or latch so that furtherretraction of the extension bar 180 will cause an abutment of the rearend of the gear rack against the forward end of the extension tube 100moving the gear rack into the position shown in FIG. 10.

This movement willswing the jaws 188-190 to a position 90 away from thatshown in FIG. 7. After this motion of the jaws, the jaws can be releasedby contact, for example, of a roller 270 on a bracket 272 with an arm274 of a limit switch 276 causing an actuation of a proper valve for theappropriate movement of the jaw-actuating piston-cylinder 200 to therelease position. While all of the piping for the cylinders has not beenshown, there are two pipes 280 and 282 which are mounted on a verticalbracket 284 on the forward end of the extension tube 100 to carry acontrol fluid to the pistoncylinder combination 200 (see FIG. 7).

Thus, in full sequence, the carriage plate 160 as viewed in FIG. 1 canmove, by actuation of piston-cylinder motor 50, on the carriage rods34-36 in a manner to synchronize with the motion of the casting machineand also to effect the proper withdrawal of the completed casting fromthe machine. When,

the carriage plate 160 is in the proper position, the arm 100 will beprojected forward in the harmonic motion provided by the arms 154 and158, this resulting from the action of the rack 168 and thepiston-cylinder assembly 172. As the projection tube 100 moves to itsoutermost position, the pistoncylinder assembly 184 (FIG. 7) will comeinto play to move the projection bar 180 outwardly; as it reaches theend of its stroke, the heel block 232 will stop at the plunger 236pulling the gear rack 214 rearwardly to swivel the jaws 188-190 to theproper pick-up position.

When this position is reached, the latch 250 will drop into the positionillustrated in FIG. 13 and lock the jaws. The jaws can then pick up thecasting from the casting machine and withdraw it to a drop position.When the tube 100 and bar 180 retract, this causes the finger 252 toenter the latch underneath the projection 256 and lift the latch to theunlocked position. At this time, further retraction of the bar 180 willcause the gear rack 214 to impact inwardly to swing the jaws to therelease position which would be 90 away from the position of the jaw asviewed in FIG. 1. Thus, the carriage, the extension tube 100 and theextension bar 180, as well as the jaws, are all synchronizedto'cooperate with a casting machine which is placed beside the assembly.

WHAT IS CLAIMED AS NEW IS:

1. A casting retrieval machine for use with automatic die castingmachines of the type having horizontally separable dies which comprises:

a. a base,

b. horizontal ways on said base,

0. spaced slides supported on said ways,

d. cross mount means supported on and spanning said slides,

e. means to move said cross mount on said slides,

i. an arm mount on said cross mount means,

g. a slide tube slidably mounted in said arm mount,

h. means on said cross-mount means for moving said slide tube in aprojection stroke transversely of said spaced slides in a harmonicmotion with the lowest acceleration and deceleration at the ends of thestroke,

i. a slide bar slidably mounted in the end of said slide tube movable toproject out of said tube in the same direction as the projection strokeof the tube, and

j. means carried by said tube to project said slide bar in a projectionstroke beyond the end of said slide tube.

2. A casting retrieval machine as defined in claim 1 in which means isinterposed between said cross mount and said arm mount to pivotallymount said arm mount on a vertical pivot post for movement in ahorizontal plane and resilient means is disposed to resist saidmovement.

3. A casting retrieval machine as defined in claim 1 in which a verticalpivot post means is provided adjacent one of said slides to pivotallymount said arm mount means on said cross mount means, and means isprovided adjacent the other of said slides to support said arm mountmeans in a swinging arc motion.

4. A casting retrieval machine as defined in claim 3 in which means isprovided to resiliently bias said am mount against said swing arcmotion.

5. A casting retrieval machine as defined 1n claim 1 in which slidebearings are provided in said arm mount for said slide tube comprising abearing housing and two pairs of opposed rollers mounted in said housingto contact the outer walls of said tube, at least one roller of eachpair being mounted on an axle, and a plurality of resilient O-ringssurrounding said axle and lodged in a recess in said housing to providea resilient mount for said axles and allow compensatory movement of saidrollers as said tube slides in said arm mount.

1. A casting retrieval machine for use with automatic die casting machines of the type having horizontally separable dies which comprises: a. a base, b. horizontal ways on said base, c. spaced slides supported on said ways, d. cross mount means supported on and spanning said slides, e. means to move said cross mount on said slides, f. an arm mount on said cross mount means, g. a slide tube slidably mounted in said arm mount, h. means on said cross-mount means for moving said slide tube in a projection stroke transversely of said spaced slides in a harmonic motion with the lowest acceleration and deceleration at the ends of the stroke, i. a slide bar slidably mounted in the end of said slide tube movable to project out of said tube in the same direction as the projection stroke of the tube, and j. means carried by said tube to project said slide bar in a projection stroke beyond the end of said slide tube.
 2. A casting retrieval machine as defined in claim 1 in which means is interposed between said cross mount and said arm mount to pivotally mount said arm mount on a vertical pivot post for movement in a horizontal plane and resilient means is disposed to resist said movement.
 3. A casting retrieval machine as defined in claim 1 in which a vertical pivot post means is provided adjacent one of said slides to pivotally mount said arm mount means on said cross mount means, and means is provided adjacent the other of said slides to support said arm mount means in a swinging arc motion.
 4. A casting retrieval machine as defined in claim 3 in which means is provided to resiliently bias said arm mount against said swing arc motion.
 5. A casting retrieval machine as defined in claim 1 in which slide bearings are provided in said arm mount for said slide tube comprising a bearing housing and two pairs of opposed rollers mounted in said housing to contact the outer walls of said tube, at least one roller of each pair being mounted on an axle, and a plurality of resilient O-rings surrounding said axle and lodged in a recess in said housing to provide a resilient mount for said axles and allow compensatory movement of said rollers as said tube slides in said arm mount. 